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Ted Mooney, P.E. RET
Pine Beach, NJ
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for Metal Finishing since 1989
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Reel-to-reel gold plating: metal builds up on masking belts
Q. Hi there!
I am a process engineer at a reel-to-reel plating shop. We are using wheel units to selectively plate gold and tin lead on connectors. We are getting a build up of metal on the masking belts which causes nodules on the parts. We see the problem with both the gold and tin lead wheel units. (We are using MSA based tin lead and standard cobalt hardened acid gold baths) Has anyone seen this type of problem? Is there any way to treat the belts to minimize the buildup?
Thanks for any help!
- Rock Hill, South Carolina
2000
A. What are the masking belts made of, Kim?
I can't exactly answer your question, but after fighting nodules on several different kinds of reel-to-reel machines recently, and seeing nodules form at the contact points regardless of whether the contacts were brushes or wheels, copper or stainless, plain or passivated, and regardless of whether this or that was floating or grounded, I do have a rule of thumb: if there is plating solution on it, it will plate. So make sure the strip, the masking belts, and the contacts are thoroughly rinsed as they leave the plating cell. 
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
April 17, 2009
A. Hi, Below is my reply according to my experience.
Ensure your masking belt must soak in gold stripper/tin stripper after use.
Do not just put your masking belt in the wheel unit when not in use. Wash and make it dry slowly in a clean environment. Hang it in a proper way.
Do not use plated dummy (leader) to pass by the masking belt. Use plastic dummy as you can. Because dummy may leave some foreign particles on the surface.
Make sure your masking belt must dry enough before go back to the solution level. Air must blow strong enough.
set up a brush system which can brush the belt surface before the belt go back to wheel unit for plating process. This system you can do it at the bottom drain location.
Ensure solution and blow-off air must be clean all the time.
Exhaust system must be strong enough to reduce the gold atmosphere in the wheel unit.
connector company - Singapore
Seeking reel-to-reel selective gold plating
RFQ: We seek a plater who can process .0321" thick C26000 H02 Temper reeled product. The parts would receive nickel allover followed by two gold zones. We could provide with a single external carrier or two external carries for masking or similar selective plating process. Alternately, we could provide a carrier in the center of the parts to allow for controlled depth plating on each end of the strip. We would need to qualify the plater quickly before sharing a print. This would probably represent approximately $40K - 80K in stamping business annually for this first part, plus gold.
Thanks.
metal stamping - York Haven, Pennsylvania, USA
May 12, 2009
Ed. note: Sorry, this RFQ is old & outdated, so contact info is no longer available. However, if you feel that something technical should be said in reply, please post it; no public commercial suggestions please ( huh? why?)
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